Aircraft: CHEETAH; TIGER; TRAVELER AA5 SERIES
Phase of flight: Final Approach
Anomaly: Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR

Flying VFR into ZZZ. At approximately 4.5 miles out I made a unicom call and declared that I was on 4.5 mile final for Runway 17. Immediately after my call; the other aircraft called that it was in the pattern for Runway 17 and was midfield on the downwind. At 3 miles out; I called 3 mile final for Runway 17. I was traveling approximately 85-90 knots and was at 900 feet AGL. Shortly after; the other aircraft called that it was turning base for Runway 17. At that point; I received a traffic alert from ADS-B and saw that our aircraft were converging on the ADS-B display. I broke off final approach with an immediate right turn and made a unicom call that I was executing a right turn to avoid traffic. The other aircraft executed a touch and go. I completed a full circle turn; reestablished on final; and executed a landing. Shortly afterwards; I approached the owner of the flight school to discuss this incident. His response was that the FAA has mandated that aircraft in the pattern ALWAYS have the right of way; and he complained that aircraft coming 'straight in' were violating FAA guidelines. I attempted to point out that the FAA regulations do not state anything near his interpretation and that common sense should rule. I specifically pointed out that Instrument Approaches are always straight in. His response was that pilots making an instrument approach should 'circle to land' and join the pattern. I tried to point out that his interpretation was going to get someone killed; because he was teaching his students to ignore any traffic 'not in the pattern.' He responded that if an accident happened then it would be the fault of the 'straight-in' traffic. I ended the conversation at that point.CFR 91.113 (g) is very clear that aircraft on final approach have the right of way. Turning from downwind to base by definition means the other aircraft was not on final. It clearly turned into me while I had the right of way. I had made two calls establishing that I was on final before the other aircraft turned into my flight path. CFR 91.113 (e) is also very clear that aircraft approaching each other 'head-on' must 'alter course to the right'. Given that I was on final at 170 degrees and the other aircraft was on a reciprocal heading (350 degrees as downwind to 17) then the other aircraft was obligated to turn right to avoid. That turn would have taken it away from final approach course. Instead; it executed a LEFT turn onto base for Runway 17. Finally; CFR 91.113 (d) is clear that 'when aircraft of the same category are converging at approximately the same altitude (except head-on; or nearly so); the aircraft to the other's right has the right-of-way.' When the other aircraft turned to base it put my aircraft to its right and established that I had the right of way under this condition.My concern is that this is the third incident I've experienced at this airport; with aircraft operated by this school; where it is clear that they are instructing student pilots to believe that they have the right of way over any traffic that is 'not in the pattern.' Given the responses to my attempt to discuss this with the school owner; it is clear he believes his interpretation is correct and that he intends to continue operating and INSTRUCTING in this manner. If this continues; then it is highly likely that a mid-air will occur; particularly under MVFR conditions when another aircraft is flying an approach to the airport and one of these school operated flights turns into that traffic. GA pilot reported a go around was required on final approach when another GA aircraft turned base and caused an airborne conflict.